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PNG Compressor

Compressing PNG is not the same job as compressing any other format, because PNG stores its data differently. Understanding what the encoder is actually doing is the difference between hitting a size target cleanly and mangling an image.

A PNG compressor works differently from every other one here, because PNG compression is lossless. No pixel is altered, so the savings come from encoding the same data more efficiently rather than from throwing anything away. That means guaranteed fidelity and a much lower ceiling on how small the file can get.

OxiPNG does the work here, testing different filter strategies per scanline and picking the best, then recompressing the result. Where an image uses a limited palette, which covers most screenshots, logos, icons and diagrams, it can also reduce the colour table, and savings of fifty to eighty percent are common.

Photographs are the case where PNG disappoints. A photograph has no repeating patterns for lossless compression to exploit, so a photographic PNG barely shrinks and remains many times larger than the same picture as a JPG. If your PNG is a photograph, converting the format will help far more than compressing it.

Everything runs in this browser tab. Add one file or several hundred, set a target size or a quality level, and the results come back without anything being uploaded.

Open the PNG compressor →

Files never leave your device
No size limits
Free, no sign-up

Frequently asked questions

How much can a PNG file realistically shrink?

For screenshots, logos and flat graphics, fifty to eighty percent is normal because lossless compression has patterns to exploit. For photographs saved as PNG, expect very little, and consider converting the format instead.

Will compressing degrade my PNG images?

No. PNG compression here is lossless, so every pixel in the output matches the input exactly. The file gets smaller purely through more efficient encoding.

Can I compress a whole folder at once?

Yes. Add as many files as you like and each is compressed independently to the same setting, then returned as a single ZIP. Processing happens on your device, so there is no upload queue and no file count limit.

Are my images uploaded anywhere?

No. The encoder runs in your browser as WebAssembly and the images never leave your device. You can confirm this in the Network tab of your developer tools while a batch is running.